81085384 has 16 divisors (see below), whose sum is σ = 152161200. Its totient is φ = 40509072.

The previous prime is 81085321. The next prime is 81085423. The reversal of 81085384 is 48358018.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8199 + ... + 15145.

It is an arithmetic number, because the mean of its divisors is an integer number (9510075).

Almost surely, 2^81085384 is an apocalyptic number.

It is an amenable number.

81085384 is a deficient number, since it is larger than the sum of its proper divisors (71075816).

81085384 is a wasteful number, since it uses less digits than its factorization.

81085384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8412 (or 8408 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 37.

The square root of 81085384 is about 9004.7423061407. The cubic root of 81085384 is about 432.8268486140.

The spelling of 81085384 in words is "eighty-one million, eighty-five thousand, three hundred eighty-four".